Answer:
The answer to your question is molality = 0.61
Explanation:
Freezing point is the temperature at which a liquid turns into a solid if a solute is added to a solution, the freezing point changes.
Data
Kf = 1.86 °C/m
molality = ?
ΔTc = 1.13°C
Formula
ΔTc = kcm
Solve for m
m = ΔTc/kc
Substitution
m = 1.13 / 1.86
Simplification and result
m = 0.61
Answer:
A chemical reaction is the change in chemical form rather than physical due to an outside force. This can come from something as simple as a change in temerature to as large as a specific element or compound.
Answer:
a) Addition reaction, is your answer
Answer:
0.133 mol (corrected to 3 sig.fig)
Explanation:
Take the atomic mass of H=1.0, and O=16.0,
no. of moles = mass / molar mass
so no. of moles of H2O produced = 1.2 / (1.0x2+16.0)
= 0.0666666 mol
From the equation, the mole ratio of H2:H2O = 2:2 = 1:1,
meaning every 1 mole of H2 reacted gives out 1 mole of water.
So, the no, of moles of H2 required should equal to the no, of moles of H2O produced, which is also 0.0666666 moles.
mass = no. of moles x molar mass
hence,
mass of H2 required = 0.066666666 x (1.0x2)
= 0.133 mol (corrected to 3 sig.fig)
Answer:
- <em>The volume of 14.0 g of nitrogen gas at STP is </em><u><em>11.2 liter.</em></u>
Explanation:
STP stands for standard pressure and temperature.
The International Institute of of Pure and Applied Chemistry, IUPAC changed the definition of standard temperature and pressure (STP) in 1982:
- Before the change, STP was defined as a temperature of 273.15 K and an absolute pressure of exactly 1 atm (101.325 kPa).
- After the change, STP is defined as a temperature of 273.15 K and an absolute pressure of exactly 105 Pa (100 kPa, 1 bar).
Using the ideal gas equation of state, PV = nRT you can calculate the volume of one mole (n = 1) of gas. With the former definition, the volume of a mol of gas at STP, rounded to 3 significant figures, was 22.4 liter. This is classical well known result.
With the later definition, the volume of a mol of gas at STP is 22.7 liter.
I will use the traditional measure of 22.4 liter per mole of gas.
<u>1) Convert 14.0 g of nitrogen gas to number of moles:</u>
- n = mass in grams / molar mass
- Atomic mass of nitrogen: 14.0 g/mol
- Nitrogen gas is a diatomic molecule, so the molar mass of nitrogen gas = molar mass of N₂ = 14.0 × 2 g/mol = 28.0 g/mol
- n = 14.0 g / 28.0 g/mol = 0.500 mol
<u>2) Set a proportion to calculate the volume of nitrogen gas:</u>
- 22.4 liter / mol = x / 0.500 mol
- Solve for x: x = 0.500 mol × 22.4 liter / mol = 11.2 liter.
<u>Conclusion:</u> the volume of 14.0 g of nitrogen gas at STP is 11.2 liter.